feat: implement git dependency support

registry/src/endpoints/package_version.rs

@@ -72,7 +72,7 @@ pub async fn get_package_version(
     let versions: IndexFile = {
         let source = app_state.source.lock().unwrap();
 
-        match source.read_file([scope, name_part], &app_state.project)? {
+        match source.read_file([scope, name_part], &app_state.project, None)? {
             Some(versions) => toml::de::from_str(&versions)?,
             None => return Ok(HttpResponse::NotFound().finish()),
         }

registry/src/endpoints/package_versions.rs

@@ -15,7 +15,8 @@ pub async fn get_package_versions(
     let (scope, name_part) = name.as_str();
 
     let source = app_state.source.lock().unwrap();
-    let versions: IndexFile = match source.read_file([scope, name_part], &app_state.project)? {
+    let versions: IndexFile =
+        match source.read_file([scope, name_part], &app_state.project, None)? {
             Some(versions) => toml::de::from_str(&versions)?,
             None => return Ok(HttpResponse::NotFound().finish()),
         };

registry/src/endpoints/publish_version.rs

@@ -142,7 +142,7 @@ pub async fn publish_package(
 
                     let (dep_scope, dep_name) = specifier.name.as_str();
                     if source
-                        .read_file([dep_scope, dep_name], &app_state.project)?
+                        .read_file([dep_scope, dep_name], &app_state.project, None)?
                         .is_none()
                     {
                         return Err(Error::InvalidArchive);
@@ -153,6 +153,11 @@ pub async fn publish_package(
                         return Err(Error::InvalidArchive);
                     }
                 }
+                DependencySpecifiers::Git(_) => {
+                    if !config.git_allowed {
+                        return Err(Error::InvalidArchive);
+                    }
+                }
             };
         }
 
@@ -161,7 +166,7 @@ pub async fn publish_package(
         let (scope, name) = manifest.name.as_str();
         let mut oids = vec![];
 
-        match source.read_file([scope, SCOPE_INFO_FILE], &app_state.project)? {
+        match source.read_file([scope, SCOPE_INFO_FILE], &app_state.project, None)? {
             Some(info) => {
                 let info: ScopeInfo = toml::de::from_str(&info)?;
                 if !info.owners.contains(&user_id.0) {
@@ -181,7 +186,7 @@ pub async fn publish_package(
 
         let mut entries: IndexFile = toml::de::from_str(
             &source
-                .read_file([scope, name], &app_state.project)?
+                .read_file([scope, name], &app_state.project, None)?
                 .unwrap_or_default(),
         )?;
 

registry/src/endpoints/search.rs

@@ -73,7 +73,7 @@ pub async fn search_packages(
 
             let mut versions: IndexFile = toml::de::from_str(
                 &source
-                    .read_file([scope, name], &app_state.project)
+                    .read_file([scope, name], &app_state.project, None)
                     .unwrap()
                     .unwrap(),
             )

src/cli/commands/add.rs

@@ -181,6 +181,9 @@ impl AddCommand {
                     dependency_key
                 );
             }
+            DependencySpecifiers::Git(_) => {
+                unreachable!("git dependencies are not supported in the add command");
+            }
         }
 
         project

src/cli/commands/outdated.rs

@@ -35,6 +35,10 @@ impl OutdatedCommand {
                     continue;
                 };
 
+                if matches!(specifier, DependencySpecifiers::Git(_)) {
+                    continue;
+                }
+
                 let source = node.node.pkg_ref.source();
 
                 if refreshed_sources.insert(source.clone()) {
@@ -50,6 +54,7 @@ impl OutdatedCommand {
                         DependencySpecifiers::Wally(ref mut spec) => {
                             spec.version = VersionReq::STAR;
                         }
+                        DependencySpecifiers::Git(_) => {}
                     };
                 }
 

src/download.rs

@@ -71,7 +71,7 @@ impl Project {
                     let (fs, target) = match source.download(&node.pkg_ref, &project, &reqwest) {
                         Ok(target) => target,
                         Err(e) => {
-                            tx.send(Err(e.into())).unwrap();
+                            tx.send(Err(Box::new(e).into())).unwrap();
                             return;
                         }
                     };
@@ -124,7 +124,7 @@ pub mod errors {
 
         /// Error downloading a package
         #[error("failed to download package")]
-        DownloadFailed(#[from] crate::source::errors::DownloadError),
+        DownloadFailed(#[from] Box<crate::source::errors::DownloadError>),
 
         /// Error writing package contents
         #[error("failed to write package contents")]

src/linking/mod.rs

@@ -88,7 +88,7 @@ impl Project {
 
                 #[cfg(feature = "roblox")]
                 if let Some(Target::Roblox { build_files, .. }) =
-                    Some(&node.target).filter(|_| !node.node.pkg_ref.is_wally())
+                    Some(&node.target).filter(|_| !node.node.pkg_ref.like_wally())
                 {
                     let script_name = ScriptName::RobloxSyncConfigGenerator.to_string();
 

src/resolver.rs

@@ -4,6 +4,7 @@ use crate::{
     names::PackageNames,
     source::{
         pesde::PesdePackageSource,
+        refs::PackageRefs,
         specifiers::DependencySpecifiers,
         traits::{PackageRef, PackageSource},
         version_id::VersionId,
@@ -176,6 +177,9 @@ impl Project {
 
                     PackageSources::Wally(crate::source::wally::WallyPackageSource::new(index_url))
                 }
+                DependencySpecifiers::Git(specifier) => PackageSources::Git(
+                    crate::source::git::GitPackageSource::new(specifier.repo.clone()),
+                ),
             };
 
             if refreshed_sources.insert(source.clone()) {
@@ -219,6 +223,8 @@ impl Project {
                     });
             }
 
+            let pkg_ref = &resolved[&target_version_id];
+
             if let Some(already_resolved) = graph
                 .get_mut(&name)
                 .and_then(|versions| versions.get_mut(&target_version_id))
@@ -230,6 +236,14 @@ impl Project {
                     target_version_id
                 );
 
+                if matches!(already_resolved.pkg_ref, PackageRefs::Git(_))
+                    != matches!(pkg_ref, PackageRefs::Git(_))
+                {
+                    log::warn!(
+                        "resolved package {name}@{target_version_id} has a different source than the previously resolved one, this may cause issues",
+                    );
+                }
+
                 if already_resolved.ty == DependencyType::Peer && ty == DependencyType::Standard {
                     already_resolved.ty = ty;
                 }
@@ -237,7 +251,6 @@ impl Project {
                 continue;
             }
 
-            let pkg_ref = &resolved[&target_version_id];
             let node = DependencyGraphNode {
                 direct: if depth == 0 {
                     Some((alias.clone(), specifier.clone()))

src/scripts.rs

@@ -43,7 +43,7 @@ pub fn execute_script<A: IntoIterator<Item = S>, S: AsRef<OsStr>, P: AsRef<Path>
         .arg("--")
         .args(args)
         .current_dir(cwd)
-        .stdin(Stdio::null())
+        .stdin(Stdio::inherit())
         .stdout(Stdio::piped())
         .stderr(Stdio::piped())
         .spawn()

src/source/git/mod.rs

@@ -0,0 +1,466 @@
+use std::{collections::BTreeMap, fmt::Debug, hash::Hash, path::PathBuf};
+
+use crate::{
+    manifest::{
+        target::{Target, TargetKind},
+        Manifest,
+    },
+    names::PackageNames,
+    source::{
+        fs::{store_in_cas, FSEntry, PackageFS},
+        git::{pkg_ref::GitPackageRef, specifier::GitDependencySpecifier},
+        git_index::GitBasedSource,
+        PackageSource, ResolveResult, VersionId,
+    },
+    util::hash,
+    Project, MANIFEST_FILE_NAME,
+};
+use gix::{bstr::BStr, traverse::tree::Recorder, Url};
+use relative_path::RelativePathBuf;
+
+/// The Git package reference
+pub mod pkg_ref;
+/// The Git dependency specifier
+pub mod specifier;
+
+/// The Git package source
+#[derive(Debug, Hash, PartialEq, Eq, Clone)]
+pub struct GitPackageSource {
+    repo_url: Url,
+}
+
+impl GitBasedSource for GitPackageSource {
+    fn path(&self, project: &Project) -> PathBuf {
+        project
+            .data_dir
+            .join("git_repos")
+            .join(hash(self.as_bytes()))
+    }
+
+    fn repo_url(&self) -> &Url {
+        &self.repo_url
+    }
+}
+
+impl GitPackageSource {
+    /// Creates a new Git package source
+    pub fn new(repo_url: Url) -> Self {
+        Self { repo_url }
+    }
+
+    fn as_bytes(&self) -> Vec<u8> {
+        self.repo_url.to_bstring().to_vec()
+    }
+}
+
+impl PackageSource for GitPackageSource {
+    type Specifier = GitDependencySpecifier;
+    type Ref = GitPackageRef;
+    type RefreshError = crate::source::git_index::errors::RefreshError;
+    type ResolveError = errors::ResolveError;
+    type DownloadError = errors::DownloadError;
+
+    fn refresh(&self, project: &Project) -> Result<(), Self::RefreshError> {
+        GitBasedSource::refresh(self, project)
+    }
+
+    fn resolve(
+        &self,
+        specifier: &Self::Specifier,
+        project: &Project,
+        _project_target: TargetKind,
+    ) -> Result<ResolveResult<Self::Ref>, Self::ResolveError> {
+        let repo = gix::open(self.path(project))
+            .map_err(|e| errors::ResolveError::OpenRepo(Box::new(self.repo_url.clone()), e))?;
+        let rev = repo
+            .rev_parse_single(BStr::new(&specifier.rev))
+            .map_err(|e| {
+                errors::ResolveError::ParseRev(
+                    specifier.rev.clone(),
+                    Box::new(self.repo_url.clone()),
+                    e,
+                )
+            })?;
+        let tree = rev
+            .object()
+            .map_err(|e| {
+                errors::ResolveError::ParseRevToObject(Box::new(self.repo_url.clone()), e)
+            })?
+            .peel_to_tree()
+            .map_err(|e| {
+                errors::ResolveError::ParseObjectToTree(Box::new(self.repo_url.clone()), e)
+            })?;
+
+        let manifest = match self
+            .read_file([MANIFEST_FILE_NAME], project, Some(tree.clone()))
+            .map_err(|e| errors::ResolveError::ReadManifest(Box::new(self.repo_url.clone()), e))?
+        {
+            Some(m) => match toml::from_str::<Manifest>(&m) {
+                Ok(m) => Some(m),
+                Err(e) => {
+                    return Err(errors::ResolveError::DeserManifest(
+                        Box::new(self.repo_url.clone()),
+                        e,
+                    ))
+                }
+            },
+            None => None,
+        };
+
+        let (name, version_id, dependencies) = match manifest {
+            Some(manifest) => {
+                let dependencies = manifest.all_dependencies().map_err(|e| {
+                    errors::ResolveError::CollectDependencies(Box::new(self.repo_url.clone()), e)
+                })?;
+                let name = PackageNames::Pesde(manifest.name);
+                let version_id = VersionId(manifest.version, manifest.target.kind());
+
+                (name, version_id, dependencies)
+            }
+
+            #[cfg(feature = "wally-compat")]
+            None => {
+                match self
+                    .read_file(["wally.toml"], project, Some(tree))
+                    .map_err(|e| {
+                        errors::ResolveError::ReadManifest(Box::new(self.repo_url.clone()), e)
+                    })? {
+                    Some(m) => {
+                        match toml::from_str::<crate::source::wally::manifest::WallyManifest>(&m) {
+                            Ok(manifest) => {
+                                let dependencies = manifest.all_dependencies().map_err(|e| {
+                                    errors::ResolveError::CollectDependencies(
+                                        Box::new(self.repo_url.clone()),
+                                        e,
+                                    )
+                                })?;
+                                let name = PackageNames::Wally(manifest.package.name);
+                                let version_id =
+                                    VersionId(manifest.package.version, TargetKind::Roblox);
+
+                                (name, version_id, dependencies)
+                            }
+                            Err(e) => {
+                                return Err(errors::ResolveError::DeserManifest(
+                                    Box::new(self.repo_url.clone()),
+                                    e,
+                                ))
+                            }
+                        }
+                    }
+                    None => {
+                        return Err(errors::ResolveError::NoManifest(Box::new(
+                            self.repo_url.clone(),
+                        )))
+                    }
+                }
+            }
+            #[cfg(not(feature = "wally-compat"))]
+            None => {
+                return Err(errors::ResolveError::NoManifest(Box::new(
+                    self.repo_url.clone(),
+                )))
+            }
+        };
+
+        let target = *version_id.target();
+        let new_structure = matches!(name, PackageNames::Pesde(_));
+
+        Ok((
+            name,
+            BTreeMap::from([(
+                version_id,
+                GitPackageRef {
+                    repo: self.repo_url.clone(),
+                    rev: rev.to_string(),
+                    target,
+                    new_structure,
+                    dependencies,
+                },
+            )]),
+        ))
+    }
+
+    fn download(
+        &self,
+        pkg_ref: &Self::Ref,
+        project: &Project,
+        _reqwest: &reqwest::blocking::Client,
+    ) -> Result<(PackageFS, Target), Self::DownloadError> {
+        let index_file = project
+            .cas_dir
+            .join("git_index")
+            .join(hash(self.as_bytes()))
+            .join(&pkg_ref.rev)
+            .join(pkg_ref.target.to_string());
+
+        match std::fs::read_to_string(&index_file) {
+            Ok(s) => {
+                log::debug!(
+                    "using cached index file for package {}#{} {}",
+                    pkg_ref.repo,
+                    pkg_ref.rev,
+                    pkg_ref.target
+                );
+
+                let fs = toml::from_str::<PackageFS>(&s).map_err(|e| {
+                    errors::DownloadError::DeserializeFile(Box::new(self.repo_url.clone()), e)
+                })?;
+
+                let manifest = match fs.0.get(&RelativePathBuf::from(MANIFEST_FILE_NAME)) {
+                    Some(FSEntry::File(hash)) => match fs
+                        .read_file(hash, project.cas_dir())
+                        .map(|m| toml::de::from_str::<Manifest>(&m))
+                    {
+                        Some(Ok(m)) => Some(m),
+                        Some(Err(e)) => {
+                            return Err(errors::DownloadError::DeserializeFile(
+                                Box::new(self.repo_url.clone()),
+                                e,
+                            ))
+                        }
+                        None => None,
+                    },
+                    _ => None,
+                };
+
+                let target = match manifest {
+                    Some(manifest) => manifest.target,
+                    #[cfg(feature = "wally-compat")]
+                    None if !pkg_ref.new_structure => {
+                        let tempdir = tempfile::tempdir()?;
+                        fs.write_to(tempdir.path(), project.cas_dir(), false)?;
+
+                        crate::source::wally::compat_util::get_target(project, &tempdir)?
+                    }
+                    None => {
+                        return Err(errors::DownloadError::NoManifest(Box::new(
+                            self.repo_url.clone(),
+                        )))
+                    }
+                };
+
+                return Ok((fs, target));
+            }
+            Err(e) if e.kind() == std::io::ErrorKind::NotFound => {}
+            Err(e) => return Err(errors::DownloadError::Io(e)),
+        }
+
+        let repo = gix::open(self.path(project))
+            .map_err(|e| errors::DownloadError::OpenRepo(Box::new(self.repo_url.clone()), e))?;
+        let rev = repo
+            .rev_parse_single(BStr::new(&pkg_ref.rev))
+            .map_err(|e| {
+                errors::DownloadError::ParseRev(
+                    pkg_ref.rev.clone(),
+                    Box::new(self.repo_url.clone()),
+                    e,
+                )
+            })?;
+        let tree = rev
+            .object()
+            .map_err(|e| {
+                errors::DownloadError::ParseEntryToObject(Box::new(self.repo_url.clone()), e)
+            })?
+            .peel_to_tree()
+            .map_err(|e| {
+                errors::DownloadError::ParseObjectToTree(Box::new(self.repo_url.clone()), e)
+            })?;
+
+        let mut recorder = Recorder::default();
+        tree.traverse()
+            .breadthfirst(&mut recorder)
+            .map_err(|e| errors::DownloadError::TraverseTree(Box::new(self.repo_url.clone()), e))?;
+
+        let mut entries = BTreeMap::new();
+        let mut manifest = None;
+
+        for entry in recorder.records {
+            let path = RelativePathBuf::from(entry.filepath.to_string());
+            let object = repo.find_object(entry.oid).map_err(|e| {
+                errors::DownloadError::ParseEntryToObject(Box::new(self.repo_url.clone()), e)
+            })?;
+
+            if matches!(object.kind, gix::object::Kind::Tree) {
+                entries.insert(path, FSEntry::Directory);
+
+                continue;
+            }
+
+            let data = object.into_blob().data.clone();
+            let hash = store_in_cas(project.cas_dir(), &data)?.0;
+
+            if path == MANIFEST_FILE_NAME {
+                manifest = Some(data);
+            }
+
+            entries.insert(path, FSEntry::File(hash));
+        }
+
+        let manifest = match manifest {
+            Some(data) => match String::from_utf8(data.to_vec()) {
+                Ok(s) => match toml::from_str::<Manifest>(&s) {
+                    Ok(m) => Some(m),
+                    Err(e) => {
+                        return Err(errors::DownloadError::DeserializeFile(
+                            Box::new(self.repo_url.clone()),
+                            e,
+                        ))
+                    }
+                },
+                Err(e) => return Err(errors::DownloadError::ParseManifest(e)),
+            },
+            None => None,
+        };
+
+        let fs = PackageFS(entries);
+
+        let target = match manifest {
+            Some(manifest) => manifest.target,
+            #[cfg(feature = "wally-compat")]
+            None if !pkg_ref.new_structure => {
+                let tempdir = tempfile::tempdir()?;
+                fs.write_to(tempdir.path(), project.cas_dir(), false)?;
+
+                crate::source::wally::compat_util::get_target(project, &tempdir)?
+            }
+            None => {
+                return Err(errors::DownloadError::NoManifest(Box::new(
+                    self.repo_url.clone(),
+                )))
+            }
+        };
+
+        if let Some(parent) = index_file.parent() {
+            std::fs::create_dir_all(parent)?;
+        }
+
+        std::fs::write(
+            &index_file,
+            toml::to_string(&fs).map_err(|e| {
+                errors::DownloadError::SerializeIndex(Box::new(self.repo_url.clone()), e)
+            })?,
+        )
+        .map_err(errors::DownloadError::Io)?;
+
+        Ok((fs, target))
+    }
+}
+
+/// Errors that can occur when interacting with the Git package source
+pub mod errors {
+    use relative_path::RelativePathBuf;
+    use thiserror::Error;
+
+    /// Errors that can occur when resolving a package from a Git package source
+    #[derive(Debug, Error)]
+    #[non_exhaustive]
+    pub enum ResolveError {
+        /// An error occurred opening the Git repository
+        #[error("error opening Git repository for url {0}")]
+        OpenRepo(Box<gix::Url>, #[source] gix::open::Error),
+
+        /// An error occurred parsing rev
+        #[error("error parsing rev {0} for repository {1}")]
+        ParseRev(
+            String,
+            Box<gix::Url>,
+            #[source] gix::revision::spec::parse::single::Error,
+        ),
+
+        /// An error occurred parsing rev to object
+        #[error("error parsing rev to object for repository {0}")]
+        ParseRevToObject(Box<gix::Url>, #[source] gix::object::find::existing::Error),
+
+        /// An error occurred parsing object to tree
+        #[error("error parsing object to tree for repository {0}")]
+        ParseObjectToTree(Box<gix::Url>, #[source] gix::object::peel::to_kind::Error),
+
+        /// An error occurred reading repository file
+        #[error("error reading repository {0} file")]
+        ReadManifest(
+            Box<gix::Url>,
+            #[source] crate::source::git_index::errors::ReadFile,
+        ),
+
+        /// An error occurred collecting all manifest dependencies
+        #[error("error collecting all manifest dependencies for repository {0}")]
+        CollectDependencies(
+            Box<gix::Url>,
+            #[source] crate::manifest::errors::AllDependenciesError,
+        ),
+
+        /// An error occurred deserializing a manifest
+        #[error("error deserializing manifest for repository {0}")]
+        DeserManifest(Box<gix::Url>, #[source] toml::de::Error),
+
+        /// No manifest was found
+        #[error("no manifest found in repository {0}")]
+        NoManifest(Box<gix::Url>),
+    }
+
+    /// Errors that can occur when downloading a package from a Git package source
+    #[derive(Debug, Error)]
+    #[non_exhaustive]
+    pub enum DownloadError {
+        /// An error occurred deserializing a file
+        #[error("error deserializing file in repository {0}")]
+        DeserializeFile(Box<gix::Url>, #[source] toml::de::Error),
+
+        /// An error occurred interacting with the file system
+        #[error("error interacting with the file system")]
+        Io(#[from] std::io::Error),
+
+        /// An error occurred while searching for a Wally lib export
+        #[cfg(feature = "wally-compat")]
+        #[error("error searching for Wally lib export")]
+        FindLibPath(#[from] crate::source::wally::compat_util::errors::FindLibPathError),
+
+        /// No manifest was found
+        #[error("no manifest found in repository {0}")]
+        NoManifest(Box<gix::Url>),
+
+        /// An error occurred opening the Git repository
+        #[error("error opening Git repository for url {0}")]
+        OpenRepo(Box<gix::Url>, #[source] gix::open::Error),
+
+        /// An error occurred parsing rev
+        #[error("error parsing rev {0} for repository {1}")]
+        ParseRev(
+            String,
+            Box<gix::Url>,
+            #[source] gix::revision::spec::parse::single::Error,
+        ),
+
+        /// An error occurred while traversing the tree
+        #[error("error traversing tree for repository {0}")]
+        TraverseTree(
+            Box<gix::Url>,
+            #[source] gix::traverse::tree::breadthfirst::Error,
+        ),
+
+        /// An error occurred parsing an entry to object
+        #[error("error parsing an entry to object for repository {0}")]
+        ParseEntryToObject(Box<gix::Url>, #[source] gix::object::find::existing::Error),
+
+        /// An error occurred parsing object to tree
+        #[error("error parsing object to tree for repository {0}")]
+        ParseObjectToTree(Box<gix::Url>, #[source] gix::object::peel::to_kind::Error),
+
+        /// An error occurred reading a tree entry
+        #[error("error reading tree entry for repository {0} at {1}")]
+        ReadTreeEntry(
+            Box<gix::Url>,
+            RelativePathBuf,
+            #[source] gix::objs::decode::Error,
+        ),
+
+        /// An error occurred parsing the pesde manifest to UTF-8
+        #[error("error parsing the manifest for repository {0} to UTF-8")]
+        ParseManifest(#[source] std::string::FromUtf8Error),
+
+        /// An error occurred while serializing the index file
+        #[error("error serializing the index file for repository {0}")]
+        SerializeIndex(Box<gix::Url>, #[source] toml::ser::Error),
+    }
+}

src/source/git/pkg_ref.rs

@@ -0,0 +1,45 @@
+use std::collections::BTreeMap;
+
+use serde::{Deserialize, Serialize};
+
+use crate::{
+    manifest::{target::TargetKind, DependencyType},
+    source::{git::GitPackageSource, DependencySpecifiers, PackageRef, PackageSources},
+};
+
+/// A Git package reference
+#[derive(Debug, Serialize, Deserialize, Clone, Eq, PartialEq)]
+pub struct GitPackageRef {
+    /// The repository of the package
+    #[serde(
+        serialize_with = "crate::util::serialize_gix_url",
+        deserialize_with = "crate::util::deserialize_gix_url"
+    )]
+    pub repo: gix::Url,
+    /// The revision of the package
+    pub rev: String,
+    /// The dependencies of the package
+    #[serde(default, skip_serializing_if = "BTreeMap::is_empty")]
+    pub dependencies: BTreeMap<String, (DependencySpecifiers, DependencyType)>,
+    /// Whether this package uses the new structure
+    pub new_structure: bool,
+    /// The target of the package
+    pub target: TargetKind,
+}
+impl PackageRef for GitPackageRef {
+    fn dependencies(&self) -> &BTreeMap<String, (DependencySpecifiers, DependencyType)> {
+        &self.dependencies
+    }
+
+    fn use_new_structure(&self) -> bool {
+        self.new_structure
+    }
+
+    fn target_kind(&self) -> TargetKind {
+        self.target
+    }
+
+    fn source(&self) -> PackageSources {
+        PackageSources::Git(GitPackageSource::new(self.repo.clone()))
+    }
+}

src/source/git/specifier.rs

@@ -0,0 +1,28 @@
+use std::fmt::Display;
+
+use serde::{Deserialize, Serialize};
+
+use crate::{manifest::target::TargetKind, source::DependencySpecifier};
+
+/// The specifier for a Git dependency
+#[derive(Debug, Serialize, Deserialize, Clone, PartialEq, Eq, Hash)]
+pub struct GitDependencySpecifier {
+    /// The repository of the package
+    #[serde(
+        serialize_with = "crate::util::serialize_gix_url",
+        deserialize_with = "crate::util::deserialize_git_like_url"
+    )]
+    pub repo: gix::Url,
+    /// The revision of the package
+    pub rev: String,
+    /// The target to use for the package
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub target: Option<TargetKind>,
+}
+impl DependencySpecifier for GitDependencySpecifier {}
+
+impl Display for GitDependencySpecifier {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        write!(f, "{}#{}", self.repo, self.rev)
+    }
+}

src/source/git_index.rs

@@ -64,6 +64,7 @@ pub trait GitBasedSource {
         &self,
         file_path: I,
         project: &Project,
+        tree: Option<gix::Tree>,
     ) -> Result<Option<String>, errors::ReadFile> {
         let path = self.path(project);
 
@@ -72,7 +73,7 @@ pub trait GitBasedSource {
             Err(e) => return Err(errors::ReadFile::Open(path, Box::new(e))),
         };
 
-        let tree = match self.tree(&repo) {
+        let tree = match tree.map_or_else(|| self.tree(&repo), Ok) {
             Ok(tree) => tree,
             Err(e) => return Err(errors::ReadFile::Tree(path, Box::new(e))),
         };

src/source/mod.rs

@@ -12,6 +12,8 @@ use crate::{
 
 /// Packages' filesystems
 pub mod fs;
+/// The Git package source
+pub mod git;
 /// Git index-based package source utilities
 pub mod git_index;
 /// The pesde package source
@@ -39,6 +41,8 @@ pub enum PackageSources {
     /// A Wally package source
     #[cfg(feature = "wally-compat")]
     Wally(wally::WallyPackageSource),
+    /// A Git package source
+    Git(git::GitPackageSource),
 }
 
 impl PackageSource for PackageSources {
@@ -53,6 +57,7 @@ impl PackageSource for PackageSources {
             PackageSources::Pesde(source) => source.refresh(project).map_err(Into::into),
             #[cfg(feature = "wally-compat")]
             PackageSources::Wally(source) => source.refresh(project).map_err(Into::into),
+            PackageSources::Git(source) => source.refresh(project).map_err(Into::into),
         }
     }
 
@@ -90,6 +95,19 @@ impl PackageSource for PackageSources {
                 })
                 .map_err(Into::into),
 
+            (PackageSources::Git(source), DependencySpecifiers::Git(specifier)) => source
+                .resolve(specifier, project, project_target)
+                .map(|(name, results)| {
+                    (
+                        name,
+                        results
+                            .into_iter()
+                            .map(|(version, pkg_ref)| (version, PackageRefs::Git(pkg_ref)))
+                            .collect(),
+                    )
+                })
+                .map_err(Into::into),
+
             _ => Err(errors::ResolveError::Mismatch),
         }
     }
@@ -110,6 +128,10 @@ impl PackageSource for PackageSources {
                 .download(pkg_ref, project, reqwest)
                 .map_err(Into::into),
 
+            (PackageSources::Git(source), PackageRefs::Git(pkg_ref)) => source
+                .download(pkg_ref, project, reqwest)
+                .map_err(Into::into),
+
             _ => Err(errors::DownloadError::Mismatch),
         }
     }
@@ -144,6 +166,10 @@ pub mod errors {
         #[cfg(feature = "wally-compat")]
         #[error("error resolving wally package")]
         Wally(#[from] crate::source::wally::errors::ResolveError),
+
+        /// A Git package source failed to resolve
+        #[error("error resolving git package")]
+        Git(#[from] crate::source::git::errors::ResolveError),
     }
 
     /// Errors that can occur when downloading a package
@@ -162,5 +188,9 @@ pub mod errors {
         #[cfg(feature = "wally-compat")]
         #[error("error downloading wally package")]
         Wally(#[from] crate::source::wally::errors::DownloadError),
+
+        /// A Git package source failed to download
+        #[error("error downloading git package")]
+        Git(#[from] crate::source::git::errors::DownloadError),
     }
 }

src/source/pesde/mod.rs

@@ -68,7 +68,9 @@ impl PesdePackageSource {
 
     /// Reads the config file
     pub fn config(&self, project: &Project) -> Result<IndexConfig, errors::ConfigError> {
-        let file = self.read_file(["config.toml"], project).map_err(Box::new)?;
+        let file = self
+            .read_file(["config.toml"], project, None)
+            .map_err(Box::new)?;
 
         let string = match file {
             Some(s) => s,
@@ -192,7 +194,7 @@ impl PackageSource for PesdePackageSource {
         project_target: TargetKind,
     ) -> Result<ResolveResult<Self::Ref>, Self::ResolveError> {
         let (scope, name) = specifier.name.as_str();
-        let string = match self.read_file([scope, name], project) {
+        let string = match self.read_file([scope, name], project, None) {
             Ok(Some(s)) => s,
             Ok(None) => return Err(Self::ResolveError::NotFound(specifier.name.to_string())),
             Err(e) => {

src/source/pesde/pkg_ref.rs

@@ -48,15 +48,3 @@ impl PackageRef for PesdePackageRef {
         PackageSources::Pesde(PesdePackageSource::new(self.index_url.clone()))
     }
 }
-
-impl Ord for PesdePackageRef {
-    fn cmp(&self, other: &Self) -> std::cmp::Ordering {
-        self.version.cmp(&other.version)
-    }
-}
-
-impl PartialOrd for PesdePackageRef {
-    fn partial_cmp(&self, other: &Self) -> Option<std::cmp::Ordering> {
-        Some(self.cmp(other))
-    }
-}

src/source/refs.rs

@@ -14,14 +14,17 @@ pub enum PackageRefs {
     /// A Wally package reference
     #[cfg(feature = "wally-compat")]
     Wally(crate::source::wally::pkg_ref::WallyPackageRef),
+    /// A Git package reference
+    Git(crate::source::git::pkg_ref::GitPackageRef),
 }
 
 impl PackageRefs {
-    /// Returns whether this package reference is a Wally package reference
+    /// Returns whether this package reference should be treated as a Wally package
-    pub fn is_wally(&self) -> bool {
+    pub fn like_wally(&self) -> bool {
         match self {
             #[cfg(feature = "wally-compat")]
             PackageRefs::Wally(_) => true,
+            PackageRefs::Git(git) => !git.use_new_structure(),
             _ => false,
         }
     }
@@ -33,6 +36,7 @@ impl PackageRef for PackageRefs {
             PackageRefs::Pesde(pkg_ref) => pkg_ref.dependencies(),
             #[cfg(feature = "wally-compat")]
             PackageRefs::Wally(pkg_ref) => pkg_ref.dependencies(),
+            PackageRefs::Git(pkg_ref) => pkg_ref.dependencies(),
         }
     }
 
@@ -41,6 +45,7 @@ impl PackageRef for PackageRefs {
             PackageRefs::Pesde(pkg_ref) => pkg_ref.use_new_structure(),
             #[cfg(feature = "wally-compat")]
             PackageRefs::Wally(pkg_ref) => pkg_ref.use_new_structure(),
+            PackageRefs::Git(pkg_ref) => pkg_ref.use_new_structure(),
         }
     }
 
@@ -49,6 +54,7 @@ impl PackageRef for PackageRefs {
             PackageRefs::Pesde(pkg_ref) => pkg_ref.target_kind(),
             #[cfg(feature = "wally-compat")]
             PackageRefs::Wally(pkg_ref) => pkg_ref.target_kind(),
+            PackageRefs::Git(pkg_ref) => pkg_ref.target_kind(),
         }
     }
 
@@ -57,6 +63,7 @@ impl PackageRef for PackageRefs {
             PackageRefs::Pesde(pkg_ref) => pkg_ref.source(),
             #[cfg(feature = "wally-compat")]
             PackageRefs::Wally(pkg_ref) => pkg_ref.source(),
+            PackageRefs::Git(pkg_ref) => pkg_ref.source(),
         }
     }
 }

src/source/specifiers.rs

@@ -11,6 +11,8 @@ pub enum DependencySpecifiers {
     /// A Wally dependency specifier
     #[cfg(feature = "wally-compat")]
     Wally(crate::source::wally::specifier::WallyDependencySpecifier),
+    /// A Git dependency specifier
+    Git(crate::source::git::specifier::GitDependencySpecifier),
 }
 impl DependencySpecifier for DependencySpecifiers {}
 
@@ -20,6 +22,7 @@ impl Display for DependencySpecifiers {
             DependencySpecifiers::Pesde(specifier) => write!(f, "{specifier}"),
             #[cfg(feature = "wally-compat")]
             DependencySpecifiers::Wally(specifier) => write!(f, "{specifier}"),
+            DependencySpecifiers::Git(specifier) => write!(f, "{specifier}"),
         }
     }
 }

src/source/wally/manifest.rs

@@ -5,12 +5,14 @@ use serde::{Deserialize, Deserializer};
 
 use crate::{
     manifest::{errors, DependencyType},
+    names::wally::WallyPackageName,
     source::{specifiers::DependencySpecifiers, wally::specifier::WallyDependencySpecifier},
 };
 
 #[derive(Deserialize, Clone, Debug)]
 #[serde(rename_all = "kebab-case")]
 pub struct WallyPackage {
+    pub name: WallyPackageName,
     pub version: Version,
 }
 

src/source/wally/mod.rs

@@ -22,7 +22,7 @@ use crate::{
     Project,
 };
 
-mod compat_util;
+pub(crate) mod compat_util;
 pub(crate) mod manifest;
 /// The Wally package reference
 pub mod pkg_ref;
@@ -60,7 +60,9 @@ impl WallyPackageSource {
 
     /// Reads the config file
     pub fn config(&self, project: &Project) -> Result<WallyIndexConfig, errors::ConfigError> {
-        let file = self.read_file(["config.json"], project).map_err(Box::new)?;
+        let file = self
+            .read_file(["config.json"], project, None)
+            .map_err(Box::new)?;
 
         let string = match file {
             Some(s) => s,
@@ -93,7 +95,7 @@ impl PackageSource for WallyPackageSource {
         _project_target: TargetKind,
     ) -> Result<crate::source::ResolveResult<Self::Ref>, Self::ResolveError> {
         let (scope, name) = specifier.name.as_str();
-        let string = match self.read_file([scope, name], project) {
+        let string = match self.read_file([scope, name], project, None) {
             Ok(Some(s)) => s,
             Ok(None) => return Err(Self::ResolveError::NotFound(specifier.name.to_string())),
             Err(e) => {

src/source/wally/pkg_ref.rs

@@ -44,15 +44,3 @@ impl PackageRef for WallyPackageRef {
         PackageSources::Wally(WallyPackageSource::new(self.index_url.clone()))
     }
 }
-
-impl Ord for WallyPackageRef {
-    fn cmp(&self, other: &Self) -> std::cmp::Ordering {
-        self.version.cmp(&other.version)
-    }
-}
-
-impl PartialOrd for WallyPackageRef {
-    fn partial_cmp(&self, other: &Self) -> Option<std::cmp::Ordering> {
-        Some(self.cmp(other))
-    }
-}

src/util.rs

@@ -61,6 +61,18 @@ pub fn deserialize_gix_url_map<'de, D: Deserializer<'de>>(
         .collect()
 }
 
+pub fn deserialize_git_like_url<'de, D: Deserializer<'de>>(
+    deserializer: D,
+) -> Result<gix::Url, D::Error> {
+    let s = String::deserialize(deserializer)?;
+    if s.contains(':') {
+        gix::Url::from_bytes(BStr::new(&s)).map_err(serde::de::Error::custom)
+    } else {
+        gix::Url::from_bytes(BStr::new(format!("https://github.com/{s}").as_bytes()))
+            .map_err(serde::de::Error::custom)
+    }
+}
+
 pub fn hash<S: AsRef<[u8]>>(struc: S) -> String {
     let mut hasher = Sha256::new();
     hasher.update(struc.as_ref());